Assistive aids for persons with reduced abilities to walk are found in many growing markets. These conventional walkers and rolling walkers utilized by many require the user to be in the standing position before the walker's physical support can be transmitted to the user by holding on to the walker by griping the sides of the walker. For persons with limited mobility, the act of standing from a sitting position is often a strenuous process, requiring the individual to pull himself up by grasping a stationary support above his sitting location or the individual must push himself up by applying a downward force on the furniture or object on which he is seated.
The prior art of assistive walking devices, going back to S. A. Darrach's, Improvement in Wheel-Crutches or Perambulators, U.S. Pat. No. 130,283, August, 1872 required the user to be in an upright standing position in order to place themselves in contact with the device's support. The introduction of a supporting seat with N. G. Bowser's, Combination Wheeled Chair and Crutch, U.S. Pat. No. 2,129,260, January, 1937 and the addition of swivel wheels by A. Comper's, Invalid Walker Unit, U.S. Pat. No. 112,691, June, 1938 aided in the support of the user but did not negate the necessity of reaching a standing position in order to gain support of the device.
Additional improvements in assistive walking devices include a crutch support with wheels as added by K. Schwartz's, Walkers' Aids, U.S. Pat. No. 2,843,180, July 1958, and improved handle supports and swivel wheels as introduced by Breyley's, Walking Aid, U.S. Pat. No. 4,046,374, September, 1977
One of the most recognized assistive devices is based on Thomas', Invalid Walker Apparatus U.S. Pat. No. 4,135,535, January, 1979, which incorporates circular bracing to increase strength and allows the user to receive support by grasping handles along sides of the device. Although innovative, this device also required the user to be in the standing position to receive support.
The addition of a foot brake to a wheeled walker with crutch supports and handles by Daughtery, Wheeled Mounted Walker with Foot Pedal Brake, U.S. Pat. No. 4,226,413, October, 1980 added to the functionality of assistive devices for users who were in the standing position.
Wheeled assistive devices continued to evolve with improvements such as a tricycle wheel placement including brake pads on multiple wheels as in Tuberville's, Walker Having Wheels and Brakes, U.S. Pat. No. 5,020,560, June, 1991 and gained further refinements with the addition of a user worn harness which supported the user as in Hoffman's, Handless Walking Aid for Preventing Falls From Loss of Balance, U.S. Pat. No. 5,152,730, October, 1992. With the advent of the ability to more easily transport and use assistive devices such as in Miller's, Foldable Walking Stabilizer Device For Physically Disabled Persons, U.S. Pat. No. 5,538,268, July, 1996 and improved handle arrangements and support Seating as in Mullholand's, Assistive Walking Device, U.S. Pat. No. 7,275,554 B2, October, 2007, the use of assistive devices has grown dramatically.
While these assistive devices are innovative in their support for the user, the user must to be in the standing position to gain support from these devices and the devices do not assist the user in reaching a standing position.
Helping the user transition between a sitting and standing position was addressed with a wheeled support and lifting sling in J. A. Rupprecht's, Walker Mechanism for Invalids, U.S. Pat. No. 2,327,671, August, 1943. This process was advanced with a refined lifting crutch and support handles in R. A. Benoit's, Invalid Lifting and Support Device, U.S. Pat. No. 3,394,933, July, 1968.
Various approaches are used to transition the user between the sitting and standing position. Fortner's, Standing Lift and Support For Wheelchair User, U.S. Pat. No. 4,948,156, August 1990 is a wheelchair apparatus which restricted forward movement of the user's knees and hips and enables the user to pull himself to the standing position by grasping a bar, moved into position by a worm gear mechanism. A refinement of this approach is Workman's, Method and System for Concentrated Primary Support for a User In Support Assistive Devices, U.S. Pat. No. 6,343,802 B2, February, 2002, which utilized a harness strapped around the user's abdomen to provide support in transition between standing and sitting postures.
Later innovations in lifting and seated support for users were introduced by Gutierrez's, Dynamic Seating and Walking Wheelchair, U.S. Pat. No. 6,619,681 B2, September, 2003 and by Razon's, Adjustable Leg Support and Seated to Stand Up Walker, U.S. Pat. No. 6,733,018 B2, May, 2004, which incorporates a hydraulic powered lifting sling to assist the user between sitting and standing.
The combined prior art of assistive devices provides stability for the user when the user is in a standing position or assists in lifting the user to a standing position or lower the user to a sitting position but, does not address the need for an assistive device that performs both the task of stable ambulatory support and assistance transitioning between sitting and standing.